Design of flyover by Manual methods

2. SUBMITTED TO:-
DEPARTMENT OF
CIVIL ENGG.
GLNAIT(MATHURA)
SUBMITTED BY:-
KRISHNA GOPAL(GL)
JITENDRA SHARMA
VIKAS KUMAR
GAURAV CHAUDHARY

3.  Design of Flyover at level crossing
No. 528 situated on NewDelhi-
Mumbai C.S.T connecting Sri
Krishna Janambhoomi Road with
NH-2 in distt. Mathura.

4.  About the Project
-Side view of Flyover
 Design of Super Structure
-Pigeaud’s Method
-Courbon’s Method
 Design of Deck Slab
 Design of Longitudinal Girders
 Design of Cross Girders
 Design of Bearing
 Design of Piers
 Design of Foundation
 Total Summary of Project
 References

5.  Total length of Flyover is 787.8m.
 Flyover consists:
-4 Different span arrangement of length
[2*23.3+17*24.0+2*12.0+19.9*1+37.9*1] c/c of
expansion
joint.
-22 Piers
-2 Abutments
 Carriage Way Width=7.5m(2 lane)
 The kerbs of width 475mm will be provide in both
directions.

6. NH2 SIDEJANMBHOOMI SIDE
P8
24m SLAB

7.  Flyover is designed for Class A loading.
 Design Speed as per AASHTO= 40kmph.
 Neoprene Bearing is used.
 Railing- Crash Barrier.
 T Cross section bridge with 3 Beam arrangement in all
spans.
 The deck slab , cross girder and longitudinal girder are
casted monolithically.

8.  Concrete grades :
- Lean Concrete M10
- Foundation M30
- Substructure M35
- Beams M40
- Deck slab M40
- Crash Barrier M40
 High yield deformed bars of Fe415 grade will be
used(IS1786).

9.  Seismic zone - IV
 Importance Factor -1.2
 Sa/g -2.5
 Bearing capacity of soil at site
- at 2.5m below G.L. =14.2T/m2
- at3.0m below G.L. =16.8T/m2
 Gradient on both side of railway portion - 1:30
 There is very little effect of centrifugal force hence it is
neglected.
 The summit and valley curves are used as vertical curves

10.  The Deck Slab and Longitudinal Girders of
superstructure are designed by two methods:
- Pigeaud’s Method(for Deck Slab)
- Courbon’s Method(for Longitudinal
girder)

11.  For slabs spanning in two directions, Pigeaud’s
Method is used, the moments in two directions
can be obtained by rational method. The use of
curves given by M. Pigeaud is recommended.
 Pigeaud’s method is applicable to rectangular
slabs supported freely on all four sides and
subjected to a symmetrical placed load.

13.  Let L and B – be the span lengths
 a and b- the dimensions of the tyre contact area in the
long and short span directions.
 u and v be the dimensions of the load spread after
allowing for dispersions through the deck slab.
 K – the ratio of short span to long span.
 M1 and M2- the moments along the short and long
span.

14.  m1 and m2- the coefficients for moments along short
and long span.
 poissons’s ratio(k) =0.15
 P- load from the wheel under consideration.
 M1 and M2 can be calculated by following equations:
M1=(m1+km2)P
M2=(m2+km1)P

15.  According to courbon’s method, the reaction Ri of the
cross beam on any girder i of a bridge consisting of
multiple parallel beams is computed by assuming a
linear variation of deflection in the transverse direction
.
 The deflection will be maximum on the exterior girder
on the side of the eccentric load and minimum on the
other exterior girder.

16. Ri= PIi/∑Ii[1+(∑Ii/∑Iidi
2)*edi]
Where,
P – total live load
e – eccentricity of live load
di– distance of girder i from the axis of
bridge
I – Moment of inertia of girder

17.  Design Data:
Effective span= 24m
Clear Roadway width for 2 lane= 7.5m
Assume 3 longitudinal beams spaced at 2.5m
c/c intervals,
7 cross beams are taken to make the slab as two-
way at 4m c/c intervals.
(the preliminary dimensions may be assumed for
simplicity)
Clear cover for reinforcement is 25mm.

18.  Thickness of slab= 250mm
 Thickness of wearing course= 75mm
 Panel size= (2.2m*3.7m)
Panel of
deck slab

21. MAXIMUM BENDING MOMENT DUE TO
DEAD LOAD
 Weight of deck slab=6.25 kN/m2
 Weight of bearing course=1.65kN/m2
 Total weight=7.9kN/m2
by Pigeaud’s curve, using the value of K and 1/K the
moment coefficients along long span and short span
(m1&m2) will be calculated .
Where,
K = short span/ long span

22. K=.594,
1/K=1.681
m1 = 0.0488,
m2= 0.015(curves)
P = 55.43
now,
M1=2.829 kNm
M2=1.237kNm

24. WHEEL 1
u = 0.6965 ,v = 0.4717,K = 0.5949
u/b = 0.3166 , v/l = 0.1275
m1 = 0.177, m2 = 0.131
Impact factor = 15%, P = 65.11kN
M1 = 12.9 kNm, M2 = 10.35kNm
WHEEL 2
M1 = 1.765kNm, M2 = 0.245kNm

25. Total moment along short span= 17.4kNm
Total moment along long span= 11.8kNm
Reinforcement:-
σcbc = 13.33 N/mm2
σst = 230N/mm2
m = 7, k = 0.711, j = 0.763, Q = 3.61
Ast1 = 561mm2, Ast2 = 415mm2
S1 = 358mm, S2 = 487mm
Provide 16mm dia bars in both directions at 300mm c/c of
bottom face.
12mm dia bars in both directions at 300mmc/c of top face.

27. Cantilever slab is designed for one-way.
Total Dead Load Moment of slab=12.4kNm
Total Live Load Moment = 37kNm
Design Moment= 49.4kNm
Ast= 1062mm2, Spacing=190mm
Provide 16mm dia bars at 180mm c/c at top face.
BM for transverse direction= .2DLM+.3LLM
= 13.6kNm
Ast= 307mm2,
Provide 12mm dia bars at 300mm c/c in transverse
direction at top face.
And provide 12mm dia bars in both directions at
250mm c/c at bottom face.

29. 1. Intermediate Longitudinal Girders
Total Dead Load Moment on Girder= 2616kNm
Reaction Factor by Courbon’s Method
Ra = 1.89w, Rb = 1.33w,Rc = 0.78w

30. I.F = 15%
Total Live Load Moment with I.F = 1460kNm
Total Design Moment = 4075kNm
Ast = 11585mm2
No. of 32mm dia bars = 14.4
Provide 15 bars of 32mm dia in 3 rows of 5 bars
each.
Provide 4 legged 8mm dia bars at 250mmc/c in
transverse direction of longitudinal girder.

31. 2. End Longitudinal Girders:
The design of end longitudinal girder is same as
intermediate girder only difference is that the live
load moment is increased by 10%.
Provide 15 bars of 32mm dia in 3 rows of 5
bars each.
Provide 4 legged 8mm dia bars at 250mmc/c in
transverse direction of End Longitudinal
Girders.

33.  Effective span for cross girder = 2.2m
 I.F.=.55
 Bending moment due to Dead Load
+ve BM = 4.581kNm
-ve BM = 8.713kNm
 BM due to Live Load
+ve BM = 29.34kNm
-ve BM = 28.37kNm

34.  Design +ve BM = 33.921kNm
 Design -ve BM = 37.083kNm
 Ast = 129mm2
 According to codal provisions, provide 3 bars of 25mm
dia. in longitudinal direction of all cross beams.
 And Provide 4 legged 12mm dia bars at 250mm c/c in
transverse direction of cross girders.
 And provide 2 bars of 22mm dia as cranked bars as
additional provision to cater to diagonal tension.

36. Design of P8
Dia of piers:-
2.5m for height above 4.5m
2.0m for height up to 4.5m
Gross Area, Ag = 4908738.521mm2
Clear cover = 40mm
Dia of longitudinal bars= 28m
Effective dia= 2446mm
Safe stress in concrete = 10N/mm2
Safe stress in steel = 230N/mm2

37. Provide 0.5% longitudinal steel of gross dia as per IRC
21:2000.
Asc = 25453.7mm2
No. of bars = 39.85
Hence privide 40 bars of 28mm.
Transverse Reinforcement:
Dia of transverse reinforcement should not less than one
quarter of longitudinal bars=7mm
Hence, take 8mm dia bars at 300mm c/c in transverse
direction.

38.  For columns height up to 4.5m:
Dia of bars = 25mm
M30 grade concrete used and Fe415 HYSD bars are used
Dia of columns = 2m
Gross Dia, Ag = 3141542.65mm2
Asc= 15707.96mm2
No. of bars = 32
Provide 32 bars of 25mm dia in longitudinal direction.
Provide 8mm dia bars at 300mm c/c in transverse direction.

40.  Assume total dead load and live load on column=
10,000kN.
 As per code provision, weight of footing is 10% of total
load on column= 1000kN
Total load in footing= 11,000kN
 Safe bearing capacity of soil= 165kN/m2
 Area of footing= 66.66m2
So provide 8.5m*10.75m= 91.375m2 area at 3m below
ground level.
And provide 9.0m*8.5m area at 2.5m below ground level.
 Isolated footing of depth 500mm at end of footing and 1.7m
near the column face.
Provide 150mm lean concrete below foundation.

42.  As per IRC6:2000, minimum Ast is 0.3% of gross dia,
so provide 0.5% of gross dia.
=24543.64mm2
Provide 25mm dia at 130mm c/c in l direction for both
cases of columns(above 4.5m and up to 4.5m)
Provide 28mm and 25mm dia bars in b direction at
130mm c/c for above 4.5m and upto 4.5m columns
respectively.

45.  Total length of flyover = 787.77m
 No. of Piers = 22 piers + 2 abutments
 Span Arrangement
- 24m*17
- 12m*2
- 23.325m*2
- 37.87m*1
- 19.87m*1
 Thickness of deck slab = 250mm
 Thickness of wearing coat = 75mm
 Depth of longitudinal girder = 1.575m
 Depth of cross girder = 1.275m
 Provide thickness of longitudinal and cross girders = 300mm

46.  SLAB 1(24m):
No. of longitudinal girder = 3(for all slabs)
No. of cross girders = 7
-Provide 16mm dia bars in both direction at 300mm c/c at bottom face.
-12mm dia bars in both direction at 300mmc/c at top face.
- Provide 16mm dia bars at 180mm c/c in cantilever portion of slab.
- Provide 12mm dia bars at 300mm c/c in transverse direction of cantilever
slab.
 LONGITUDINAL GIRDER:
- Provide 15 bars of 32mm dia in 3 rows at bottom of the T rib.
- Provide 4 legged 8mm dia bars at 250mmc/c in transverse direction.
- Provide 6 bars of 22mm dia as additional provision to cater to diagonal
tension.

47.  CROSS GIRDERS:
Provide 3 bars of 25mm dia in all cross beams.
Provide 4 legged stirrups of 10mm dia bars at 150mm c/c.
Provide 2 bars of 22mm dia as cranked bars as additional
provision to cater to diagonal tension.
 PIER:
Dia of pier = 2m (height up to 4.5m)
Dia of pier = 2.5m(height above 4.5m)
Provide 40 longitudinal bars of 28mm dia (for height above
4.5m) 8mm dia bars at 300 mm c/c for transverse reinforcement.
Provide 40 longitudinal bars of 25mm dia and 8mm dia bars at
300 mm c/c for transverse reinforcement(for height up to 4.5m)

48.  FOUNDATION:
Provided area of foundation
= 10.75m*8.5m (for height above 4.5m)
= 9m*8.5m (for height up to 4.5m)
Provide 25mm dia bars at 130mm c/c in longitudinal
direction of footing.
Provide 28mm dia bars at 130mm c/c in transverse
direction of footing.

49.  Essentials of bridge engineering:-
by D. Johnson Victor
 Design of reinforced concrete structure:-
by S. Ramamrutham
 IS codes:-
IRC:6-2000
IRC:21-2000
IRC:38-1988
IS:456-2000
IS:1786